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WHICH IS BETTER - 6 or 12 VOLTS?

THANK YOU! - For taking the time to view this page.

If you are using this information to decide if 12 volts is the way to go for an antique car, the answer is nearly always, YES. A car has many more accessory circuits. Getting modern 12 volt accessories to work on a 6 volt system is often more trouble than it is worth. In most cases, the only good reason NOT to go with a 12 volt system on a CAR, is if you are doing a complete original RESTORATION, or you are worried about losing originality points in a car show.

However, if you are working on an old TRACTOR, there are many more good reasons to leave it as a 6 volt system. So, before you start stripping the nearly indestructablevintage generator and 6 volt wiring off your antique tractor, let's make sure you are doing this for the right reasons.

What I will try to do is provide an unbiased view of both sides of the 6 Volt vs 12 Volt conversion issue as it applies to Antique Tractors. My current preference is to leave them as 6 volt positive ground systems.

There are a lot of very strong opinions on both sides, and both sides have very good points to make. Here are a few pros-and-cons:

WHY WOULD WE WANT TO DO A 12 VOLT CONVERSION?

1—The entire motor vehicle industry moved to standard 12 volt electrical systems about 50 years ago for some very good reasons. If everything else is equal, 12 volt systems are more reliable and require less frequent maintenance than 6 volt systems.

2—Most modern accessories are intended for use on 12 volt systems. If you plan to have more than the ignition and a few lights on your tractor, the original 6 volt system will quickly be overwhelmed. The generator on these old tractors only puts out about 18 Amps at 1650 RPM. The most I have seen on my amp gauge is about 12 amps. Maybe my generator is a bit tired? Compare that to 60 or more amps out of a properly-wired alternator!

3—If you frequently operate your tractor at night, headlights and taillights are usually much brighter with a 12 volt system. More power can be delivered over the same wire size, and you can use much higher wattage bulbs because you have more power available from an alternator.

4—Jump-Starting is more straightforward when the voltage and ground on both vehicles match.

5—Your 6 volt starter will crank the engine much faster at 12 volts. This makes it easier to start a nearly worn-out engine with low-compression. This may allow you to put-off doing tune-ups or even an engine rebuild.

6—If you are "points challenged" and want to spend the money for the breakerless setup, there are a couple of breakerless electronic conversions available for both 6 and 12 Volt tractors. These allow you to do away with the points and condenser inside the distributor in favor of a more modern and theoretically more-reliable breakerless setup. The 12 volt version seems to be the least troublesome of the two.

7—Good quality 6 volt replacement parts are getting harder to find.

8—There are several 12 Volt Conversion kits available, but if you have a 12 volt donor vehicle available, you might be able to do your conversion for less cost.

WHY WOULD WE WANT TO KEEP THE WEAK, OLD 6 VOLT SYSTEM?

1—There is nothing inherently wrong with a 6 volt system. Millions of very reliable vehicles were produced for many many years before 12 volt systems became the standard. None of those vehicles should be considered defective, just because they have 6 volt electrical systems. The modern standard for automobiles is currently being changed again. The new standard may be 24, 36, or as much as 48 volts! Do you think your current 12 volt vehicle will suddenly become less reliable than it is now? If you are planning to rewire your 12 volt car for 48 volts, let me know how that goes.

2—Converting to 12 volts will not fix a bad starter, solenoid, switches, ignition, or wiring. In fact, doubling the voltage will often cause some less-than-perfect parts to immediately fail.

3—Converting to 12 volts will not fix a tractor that has not been properly maintained. If it was not reliable at 6 volts, it will not suddenly become more reliable just because you converted it to 12 volts. Most of the problems people are having with 6 volt systems are caused by poor maintenance. The additional maintenance necessary to keep a 6 volt electrical system working properly costs nothing more than a little time to take apart and shine connections. Those same faulty connections will also cause a 12 volt system to fail, it just takes a little longer and then usually burns up more stuff due to the higher voltage. The 18 amps available from yoru generator might let the magic smoke out of a few parts. Run 100 amps or more from an alternator through the same failed component, and the fireworks can be really impressive! Instead of a little smoke we now have flames!

4—The original 6 volt system on your tractor has been working just fine for 50+ years. With a little maintenance, and occasional repairs, the system could certainly continue to function properly for another 50+ years.

5—The 12 volt conversion will always cost more than simply fixing the existing 6 volt system. Even if you can steal most of the 12 volt parts from a donor vehicle.

6—After digging through the archives of various forums dedicated to antique vehicles of many different types, it became obvious to me that problems with 12 volt conversions far outnumber 6 volt problems. Why? Partly because there is no such thing as a "standard" 12 volt conversion. There are several conversion kits and a few professional class conversion jobs that work well, and are reliable. But there are literally hundreds (maybe even thousands) of attempted conversions that don't work at all! As of this update, I still average two emails a week from people trying to get their 12 volt conversion to work. Compare that to one email per year with a 6 volt problem!

7—Durability–None of the alternators being used on conversions are as robust and bullet-proof as that simple old 6 Volt generator. Look at it, you are trading a sealed generator unit with a solid steel case for an alternator with an open, ventilated aluminum case. Most alternators appear to be designed for applications with some protection from weather. Water running off the hood got into the guts of my brand new Alternator on the 48. The alternator guts were completely rusty and dead in 9-months!

8—Breakerless? To the purist, this modern technology has no place on an antique vehicle. But, let's face it, the reason we see so few 8N tractors at shows, is that most of them are still "working tractors". They have a job to do and anything that could potentially increase reliability is at least worth a look. Simple economics says I can replace points 5 to 10 times for what one breakerless setup costs. A set of points should last at least a year and most go a lot longer than that. Anything over 5-year payback is hard to sell but some people claim much better reliability with the breakerless setup. My 6 Volt 1952 8N tractor, with a set of points that were new in June 2006, started on the first try every time, and didn't need new points until October 2013! I do run a point file through the points and check/set the gap about twice a year.

RELIGION

OK, here comes the religious part, you have been warned. Occasional maintenance is good for your soul. One of the reasons I like these old tractors is that I can do things like fiddle with the points, and turn screws on the carb. Very few things in life are as satisfying as chugging down your driveway on a machine you fixed yourself. Even major repairs on one of these tractors can be performed by just about anyone.

If you happen to have an aptitude for things mechanical, reading instructions is optional. There is magic in knowing what goes on inside a piece of machinery from hands-on experience. When you know how something works, and what it takes to repair it, you are less likely to abuse it. When you become more familiar with a machine, you begin to better understand it's limitations, and automatically become a safer operator.

Modern automobiles have become more reliable and require less-frequent maintenance, but at what cost? We have traded inexpensive maintenance procedures for less frequent but MUCH more expensive repairs. A well-maintained, easy-to-repair vehicle will last longer. Your 8N tractor will very likely still be chugging away and making people smile for another 50 plus years. That new shiny SUV you just bought will have been crushed, recycled, and forgotten.

This is a very abbreviated version of both sides of this argument. The actual list of pros-and-cons seems almost endless. It has not been my intent to try and force anyone in either direction. Hopefully this web page will help someone make a more intelligent decision.

I did not do that when I bought my first 8N tractor. Before I got it home, I had already decided I was going to convert it to 12 volts. Why? Frankly, I didn't do any research to see if there was any other option. The wiring on my "new" tractor was a complete mess. Rather than asking questions, and researching what I was about to do, I simply assumed the 12 Volt system would be better. The 6 volt, positive-ground system was a mystery to me, and I was not even looking for reasons to justify upgrading to a 12 volt system. Looking back, I really did not give the 6 volt system a chance or much thought. I was familiar with 12 volt systems, and honestly believed it was a no-brainer to do the 12 volt conversion.

Now that I have been down that road, for most 8N tractors, I would apply the KISS principle and stay with the original 6 volt system.

Honestly, it is totally up to you to evaluate your tractor and your needs. Either way you decide to go will not hurt my feelings a bit. At the end of the day, IT's YOUR TRACTOR.

When someone contacts me to help fix wiring problems, we usually spend more than a few minutes just figuring out what they have. With either 6 or 12 Volt systems it is often easier to pull all the wires off and start over. Thankfully, there are only about nine or ten wires on one of these tractors, so even a complete rewire is only about a $25 job.

With either 6 or 12 Volts, when you have problems with your electrical system, it is always MUCH easier to get help if your wiring is as close to original as possible.

6 VOLT TIPS AND TROUBLE-SHOOTING

Clean every terminal and connection before you do anything! Take apart and use a small flat file to shine up faces of nuts and terminals where current is supposed to flow. Replace nuts and washers at the first sign of corrosion with new zinc-plated hardware. Do not use stainless steel or copper hardware, it will cause any steel it touches to corrode much faster!

Replace your ignition switch.

Make sure your battery cables are the correct size for 6 volts. Skinny 12 volt automotive type cables are useless.

If the starter still seems slow, make sure the mating surface between the starter housing and the cast iron block is clean and shiny. Do not depend on just the mounting bolts to provide a good current path.

Make sure you are using copper wire core spark plug wires, not the automotive resistor core wires.

Replace your ignition switch.

Running ground wires from head lights and tail lights to the same ground stud where the battery is grounded will make a huge improvement in the brightness.

All switches should be checked with a decent ohm meter to make sure they are in good condition. They have typically spent years out in all sorts of weather and frequently are the source of many electrical problems. If you find any resistance across a switch, replace it.

If you got here from a link on another page, use your browsers BACK button to go back to where you were.

If you are looking for more information on wiring and wiring harnesses, you might find what you want on my general wiring page HERE., kl. If you have decided 12 volts is right for your tractor click HERE to go to the 12 volt conversion page.

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Content and Web Design by K. LaRue — This Site Was Last Updated 19 SEP 2017.
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